"X11 connection rejected because of wrong authentication."

A brief note for posterity: if you are getting an error like the following,

X11 connection rejected because of wrong authentication.
xterm Xt error: Can't open display: localhost:10.0

one thing you might try, after you have eliminated the usual suspects (no, try those first, really), is unsetting the XAUTHORITY environment variable:


* * *

The remainder of this post is a followup to my previous post, Stupid Screen Tricks. (The setup I described therein is still alive and well.)

I received the above error when I started a screen session on display :0.0 and (after disconnecting and reconnecting) subsequently tried to launch, from within it, a new X program on a different display (even after setting DISPLAY). The session inherits the old XAUTHORITY value, which, for whatever reason, for as long as it is present, foils attempts to run programs on other displays.

To work around this, I changed my here utility alias to the following,

alias here='unset XAUTHORITY; DISPLAY=`cat ~/.last-display`'

that is, unsetting XAUTHORITY as well as setting DISPLAY before trying to run anything.

Assorted notes

  • Hugin, the panorama-stitching tool, is quite slick these days (ever since it got some UI improvements in release 2010.4.0 or so, I believe). It handled perhaps 80-90% of the panoramas from my recent trip in about 3 clicks and without manual intervention. Hats off to the Hugin developers.
  • I've been learning how to twiddle the "Projection" knob in Hugin, which lets you change the geometry of the resulting panorama. For example, for photos of murals (or tapestries, or other long, flat, surfaces), the Rectlinear projection corrects for the distortion to reconstitute the "flat" image, as if you were standing far away.

Default (cylindrical)

Corrected (rectilinear)

  • Ubuntu has these new scrollbars with invisible scroll handles. They are quite annoying (being invisible and all). You can revert to the old ones like so:

    sudo apt-get remove overlay-scrollbar liboverlay-scrollbar-0.1-0